This is part of my 15 minute focus series. Children get an introduction to the human skeleton, what bones fo for us and how joints are helpful. They do an experiment trying to pick up small things without bending their fingers.

Objective: children can talk about how joints bend.

Supplies:

• Dem Bones or other book about the human skeleton
• Optional: Tools or toys that show “joints”. Things with hinges.
• Small things to pick up (or writing utensils and paper)
• craft sticks and tape

Book and Demo

While they finished up lunch, I read the book Dem Bones. (Video preview.) As I read about each joint, I had them use theirs – like wiggling toes and then bending/flexing their foot when we read about the toe bone and the ankle bone.

Optional: To better illustrate how our bodies work, I used a hinged Lego door and a busy board door to show how some joints (like knees and elbows) bend one way but not the other. I used the Zoob building toy to illustrate ball and socket joints. And I used two pencils side by side to show how the two bones in your lower arm pivot around each other when you twist your wrist.

Activity

Then I gave them some small items (pompoms, feather, a bit of yarn), and encouraged them to show me if they could pick them up. (As four year olds, they can all pick up all these items, but I think they also have a sense that they used to not be able to do this, so are a little proud of themselves for this skill.)

I helped them notice the pincer grasp – how they have to bend the index finger and thumb toward each other to create it to help them pick things up. Then I asked “what would happen if you couldn’t bend your finger?” I taped a popsicle stick to the back of each child’s index finger to hold it straight. Then we tried picking things up and tried holding a pencil. It was really hard! (The funny part was that while our older 4 year olds and 5’s did this experiment and really had a-ha moments, our younger 4’s would just use the other untaped hand to do the job. When I told them to use their taped hand, they looked quizzically at me with a “why would I do that” expression.)

We untaped their fingers, and I had them practice using scissors or tweezers for a moment, and had them notice how their thumb moves away from their fingers to do that work. We talked about opposable thumbs and that many animals don’t have them. I asked “what would it be like not to have an opposable thumb?” Then we taped their thumbs to the side of their hands, and tried doing a variety of tasks (scissors, folding paper, writing, Duplos, tearing tape, taking a lid off a water bottle and putting a straw in). I also had a toddler busy board they could try.

With older children who have a good pencil grasp, you could also have them try to write with fingers or thumb taped. My four year olds are still learning pencil grasp without their fingers taped!

Most of the kids really enjoyed the activity and got a lot out of it. A few really disliked the experience of having their finger taped and thus having limited mobility and they opted out of taping their thumbs, which I OK’ed, because bodily consent is important to respect.

Find more Human Body and Skeleton themed activities.